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<head><meta charset="utf-8"><title>steering meeting 2019-06-28 · t-compiler · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/index.html">t-compiler</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html">steering meeting 2019-06-28</a></h3>

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<a name="169172620"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169172620" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169172620">(Jun 27 2019 at 20:30)</a>:</h4>
<p>So we need to discuss a possible immediate backport of <a href="https://github.com/rust-lang/rust/pull/61207" target="_blank" title="https://github.com/rust-lang/rust/pull/61207">https://github.com/rust-lang/rust/pull/61207</a>  to 1.36.0 stable due to forward compat concerns with the second to last case in <a href="https://gist.github.com/nikomatsakis/c5c8e585989924e8485df48ab6bbc3dd" target="_blank" title="https://gist.github.com/nikomatsakis/c5c8e585989924e8485df48ab6bbc3dd">https://gist.github.com/nikomatsakis/c5c8e585989924e8485df48ab6bbc3dd</a></p>



<a name="169172639"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169172639" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169172639">(Jun 27 2019 at 20:30)</a>:</h4>
<p>cc <span class="user-mention" data-user-id="116083">@pnkfelix</span> <span class="user-mention" data-user-id="127859">@Taylor Cramer</span> <span class="user-mention" data-user-id="116009">@nikomatsakis</span></p>



<a name="169172644"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169172644" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169172644">(Jun 27 2019 at 20:31)</a>:</h4>
<p>and <span class="user-mention" data-user-id="121055">@Pietro Albini</span></p>



<a name="169172662"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169172662" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169172662">(Jun 27 2019 at 20:31)</a>:</h4>
<p>(for tomorrow)</p>



<a name="169172669"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169172669" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Pietro Albini <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169172669">(Jun 27 2019 at 20:31)</a>:</h4>
<p>and <span class="user-mention" data-user-id="116122">@simulacrum</span></p>



<a name="169172682"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169172682" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Pietro Albini <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169172682">(Jun 27 2019 at 20:31)</a>:</h4>
<p>especially because I'm not sure if I'll able to be online that much tomorrow</p>



<a name="169172684"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169172684" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169172684">(Jun 27 2019 at 20:31)</a>:</h4>
<p>I might as well cc <span class="user-group-mention" data-user-group-id="492">@T-compiler</span>, right?</p>



<a name="169173093"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169173093" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169173093">(Jun 27 2019 at 20:36)</a>:</h4>
<p>Some context:<br>
- We discussed this on the language team meeting today. Attendance was me, Felix, Taylor, and Josh. Our conclusion was to attempt a backport.<br>
- This is particularly problematic due to case 7 and 10 being weird together.<br>
- This was tested on crater with zero regressions.</p>



<a name="169173184"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169173184" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169173184">(Jun 27 2019 at 20:37)</a>:</h4>
<p><span class="user-mention" data-user-id="119009">@eddyb</span> seems to have already reviewed the PR; they said:</p>
<blockquote>
<p>I like how simple this is!</p>
</blockquote>
<p>However, it would be good if as many as possible can give the PR a thorough review and add additional test cases if you believe it to be necessary.</p>



<a name="169173215"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169173215" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169173215">(Jun 27 2019 at 20:37)</a>:</h4>
<p>Ideally that should happen ASAP because we need this done before the 30th is over</p>



<a name="169174486"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169174486" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169174486">(Jun 27 2019 at 20:54)</a>:</h4>
<p>(I will note that I did express a slight misgiving, in the sense of "it doesn't seem like it would be the end of the world to not have this backport"; but I do appreciate the motivation that with the stabilization of the Future API's, code like this will become more commonplace)</p>



<a name="169174536"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169174536" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169174536">(Jun 27 2019 at 20:55)</a>:</h4>
<p>and I think <span class="user-mention" data-user-id="127859">@Taylor Cramer</span> made the point that it <em>would</em> be a disaster to not address this &lt;= the point when async-await is stabilized.</p>



<a name="169175010"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169175010" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Taylor Cramer <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169175010">(Jun 27 2019 at 21:01)</a>:</h4>
<p>Yeah, it for sure needs to be in by 1.37 / 1.38, but missing 1.36 probably isn't the end of the world</p>



<a name="169196349"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169196349" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> simulacrum <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169196349">(Jun 28 2019 at 04:01)</a>:</h4>
<p>I won't personally be able to manage backporting until Saturday (which is technically not too late, but gives us essentially no margin for error). I am not against backporting, really, especially given crater run. I would backport directly onto stable branch... we might need to delete artifacts for them to get properly copied to dev-static, but that can happen at any point: we always publish to rust-ci-2(naming?) bucket first IIRC.</p>



<a name="169196411"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169196411" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> simulacrum <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169196411">(Jun 28 2019 at 04:03)</a>:</h4>
<p>(I will not be able to attend tomorrow's meeting either -- unfortunately -- but don't block on me for any decisions wrt to backport)</p>



<a name="169219797"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169219797" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169219797">(Jun 28 2019 at 12:22)</a>:</h4>
<p>Let me try to find a better way to summarize the results here. I am concerned that the PR doesn't have the behavior I think we want, but I want to double check.</p>



<a name="169219926"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169219926" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169219926">(Jun 28 2019 at 12:25)</a>:</h4>
<p>at the T-lang meeting last night, <span class="user-mention" data-user-id="127859">@Taylor Cramer</span> said several times that they did not understand, in <a href="https://gist.github.com/nikomatsakis/c5c8e585989924e8485df48ab6bbc3dd" target="_blank" title="https://gist.github.com/nikomatsakis/c5c8e585989924e8485df48ab6bbc3dd">your gist</a>, why lines 2+3 have differing static semantics under "Niko's (preferred?) rule"</p>



<a name="169220004"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169220004" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169220004">(Jun 28 2019 at 12:26)</a>:</h4>
<p>and more generally, the group at large seemed to basically say that "Niko's rule" is a non-starter due to its regressing behavior for lines 2 and 5.</p>



<a name="169220025"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169220025" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169220025">(Jun 28 2019 at 12:27)</a>:</h4>
<p>So, <span class="user-mention" data-user-id="116009">@nikomatsakis</span> , you may want to spell out somewhere what you see as the motivation/justification for "Niko's rule", if that is indeed what you want.</p>



<a name="169220034"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169220034" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169220034">(Jun 28 2019 at 12:27)</a>:</h4>
<p>(Also, it would probably be good to add explicit row numbers to that table. It was very annoying trying to describe the entries last night.)</p>



<a name="169220160"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169220160" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169220160">(Jun 28 2019 at 12:29)</a>:</h4>
<p>Yeah, no, Niko's rule wasn't meant to be seen by the public =)</p>



<a name="169220166"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169220166" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169220166">(Jun 28 2019 at 12:29)</a>:</h4>
<p>actually the gist itself wasn't really ready</p>



<a name="169220234"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169220234" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169220234">(Jun 28 2019 at 12:30)</a>:</h4>
<p>You didn't hold onto your <code>&amp;mut gist</code> long enough.</p>



<a name="169220717"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169220717" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169220717">(Jun 28 2019 at 12:37)</a>:</h4>
<p>OK, I will revamp the table, but I think my take is that the PR is indeed an improvement, but I think we may want to deprecate some of the things that we currently accept</p>



<a name="169220740"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169220740" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169220740">(Jun 28 2019 at 12:37)</a>:</h4>
<p>I just did some more testing, but I have to run right now</p>



<a name="169222421"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169222421" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169222421">(Jun 28 2019 at 13:02)</a>:</h4>
<p>OK here is a <a href="https://gist.github.com/nikomatsakis/5996e4f58899ef5c6926948b6f76835e" target="_blank" title="https://gist.github.com/nikomatsakis/5996e4f58899ef5c6926948b6f76835e">revised gist</a> that I believe is accurate.</p>



<a name="169222890"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169222890" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169222890">(Jun 28 2019 at 13:08)</a>:</h4>
<p>(I assume <code>X</code> means "rustc issues an error due to ambiguous lifetime")</p>



<a name="169223971"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169223971" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169223971">(Jun 28 2019 at 13:23)</a>:</h4>
<p>S3 and N1 are symmetrical. Only change is Pin to Box.</p>



<a name="169224026"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169224026" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169224026">(Jun 28 2019 at 13:24)</a>:</h4>
<p>And the mut bit but that's irrelevant</p>



<a name="169226901"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169226901" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169226901">(Jun 28 2019 at 14:01)</a>:</h4>
<blockquote>
<p>S3 and N1 are symmetrical. Only change is Pin to Box.</p>
</blockquote>
<p>this is intentional :)</p>



<a name="169226934"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169226934" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169226934">(Jun 28 2019 at 14:01)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> but why does it say X then?</p>



<a name="169226947"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169226947" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169226947">(Jun 28 2019 at 14:01)</a>:</h4>
<p>hello <span class="user-group-mention" data-user-group-id="897">@T-compiler/meeting</span></p>



<a name="169227010"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227010" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227010">(Jun 28 2019 at 14:02)</a>:</h4>
<blockquote>
<p><span class="user-mention silent" data-user-id="116009">nikomatsakis</span> but why does it say X then?</p>
</blockquote>
<p>(correct, typo, should be <code>self</code> for 61207)</p>



<a name="169227022"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227022" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227022">(Jun 28 2019 at 14:02)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> phew <span aria-label="slight smile" class="emoji emoji-1f642" role="img" title="slight smile">:slight_smile:</span></p>



<a name="169227031"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227031" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227031">(Jun 28 2019 at 14:02)</a>:</h4>
<p>the world is alright again</p>



<a name="169227043"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227043" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227043">(Jun 28 2019 at 14:03)</a>:</h4>
<p>So I'd like to establish up front</p>



<a name="169227052"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227052" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227052">(Jun 28 2019 at 14:03)</a>:</h4>
<blockquote>
<p>(I assume <code>X</code> means "rustc issues an error due to ambiguous lifetime")</p>
</blockquote>
<p>actually it's that it gets a kind of "unrelated error" -- I was just double checking the behavior in weird cases</p>



<a name="169227128"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227128" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227128">(Jun 28 2019 at 14:04)</a>:</h4>
<p>I'd like to establish up front whether we plan to have the topic of this meeting <em>change</em> to discussion of the last minute backporting of <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a>, or if we are planning to bound how much time we spend discussing that</p>



<a name="169227147"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227147" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227147">(Jun 28 2019 at 14:04)</a>:</h4>
<p>(imo <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a> should take as much time as is necessary)</p>



<a name="169227154"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227154" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227154">(Jun 28 2019 at 14:04)</a>:</h4>
<p><span class="user-mention" data-user-id="126931">@centril</span>  I think you are missing my point</p>



<a name="169227182"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227182" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227182">(Jun 28 2019 at 14:05)</a>:</h4>
<p>if we anticipate that it will take up the whole meeting slot, then fine</p>



<a name="169227201"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227201" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227201">(Jun 28 2019 at 14:05)</a>:</h4>
<p>but there are people who may be interested in the triage/maintenance issues who might not be as interested in the particulars of this</p>



<a name="169227225"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227225" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227225">(Jun 28 2019 at 14:05)</a>:</h4>
<p>Out of respect for those people's time, I would like to at least try to <em>guess</em> whether this is going to be a "quick" 5-10 minute thing</p>



<a name="169227285"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227285" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227285">(Jun 28 2019 at 14:06)</a>:</h4>
<p>or if we simply need to punt on the triage/maintenance discussion, due to the timing pressure that we have for this backport question</p>



<a name="169227392"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227392" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227392">(Jun 28 2019 at 14:07)</a>:</h4>
<p>So I think we have 2 issues to think about:<br>
1. Do we think the PR is a step in the right direction?<br>
2. Do we backport to 1.36.0, to 1.37.0, are we fine with 1.38.0?</p>



<a name="169227420"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227420" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227420">(Jun 28 2019 at 14:07)</a>:</h4>
<p>Possibly:<br>
3. Is there any way in which the PR is a step in the wrong direction?</p>



<a name="169227522"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227522" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227522">(Jun 28 2019 at 14:08)</a>:</h4>
<p>I don't know how much that will take; but 8 minutes have already passed, so let's not waste more time.</p>



<a name="169227538"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227538" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227538">(Jun 28 2019 at 14:08)</a>:</h4>
<p>Okay then, based on this, I'm willing to guess that this <em>will</em> take up the whole meeting slot. <span class="user-mention" data-user-id="116009">@nikomatsakis</span> , what do you think? Should we officially change the topic of the whole meeting to be about <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a> slash dealing with <code>Pin</code> and lifetime elision?</p>



<a name="169227595"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227595" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227595">(Jun 28 2019 at 14:09)</a>:</h4>
<p>Sure, why not.</p>



<a name="169227753"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227753" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227753">(Jun 28 2019 at 14:11)</a>:</h4>
<p>okay</p>



<a name="169227764"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227764" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227764">(Jun 28 2019 at 14:11)</a>:</h4>
<p>Here is my understanding of the function elision rules based on the gist, the reference, some tests, the code in the PR, etc..</p>
<hr>
<p>1. Each elided lifetime in the parameters becomes a distinct lifetime parameter.<br>
2. If there is exactly one lifetime used in the parameters (elided or not), that lifetime is assigned to all elided output lifetimes.<br>
In method signatures there is another rule:</p>
<ul>
<li>
<p>STABLE: If the receiver has the semantic type <code>&amp;'lt mut? Self</code>, then <code>'lt</code> is assigned to all elided output lifetime parameters.</p>
</li>
<li>
<p>WITH PR: In the receiver, if there is a unique mention of the semantic type <code>&amp;'lt mut? Self</code>, then <code>'lt</code> is assigned to all elided output lifetime parameters.</p>
</li>
</ul>



<a name="169227845"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227845" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227845">(Jun 28 2019 at 14:12)</a>:</h4>
<p>So yes let's start with describing the behavior. I don't think that fully meets the tests</p>



<a name="169227848"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227848" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227848">(Jun 28 2019 at 14:12)</a>:</h4>
<p>That is, on stable we just look at the type expression of the receiver; with the PR we look at any type expression inside the receiver</p>



<a name="169227868"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227868" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227868">(Jun 28 2019 at 14:12)</a>:</h4>
<p>Notably, this case does not behave as described:</p>
<p><code>impl Foo&lt;'a&gt; { fn(self: Box&lt;Foo&lt;'a&gt;&gt;, f: &amp;u8) -&gt; &amp;u8 }</code></p>



<a name="169227913"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227913" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227913">(Jun 28 2019 at 14:13)</a>:</h4>
<p>under both stable and <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a>, this resolves the <code>-&gt; &amp;u8</code> to the type of <code>f</code></p>



<a name="169227947"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227947" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227947">(Jun 28 2019 at 14:13)</a>:</h4>
<p>and yet there are multiple lifetimes (so rule 2 does not apply) and there is no <code>&amp;Self</code> (so self rule does not apply)</p>



<a name="169227977"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227977" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227977">(Jun 28 2019 at 14:13)</a>:</h4>
<p>I do not however necessarily think that has to block the PR</p>



<a name="169227991"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169227991" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169227991">(Jun 28 2019 at 14:13)</a>:</h4>
<p>Because (as I said) it is also the behavior on stable</p>



<a name="169228053"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228053" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228053">(Jun 28 2019 at 14:14)</a>:</h4>
<p>(I am running one other test re: the PR which seems a bit odd; in particular, the PR uses an "awfully shallow" test to decide if <code>&amp;Self</code> has been found, though stable does as well)</p>



<a name="169228100"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228100" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228100">(Jun 28 2019 at 14:15)</a>:</h4>
<p>I think this could only ever be an issue, however, under the more generalized forms of arbitrary-self-types</p>



<a name="169228117"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228117" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228117">(Jun 28 2019 at 14:15)</a>:</h4>
<p>So it also not likely to be a blocker to backporting</p>



<a name="169228236"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228236" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228236">(Jun 28 2019 at 14:16)</a>:</h4>
<p>I did notice the tests in your gist did not include more complex compositions such as <code>Box&lt;Box&lt;Foo&gt;&gt;</code></p>



<a name="169228254"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228254" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228254">(Jun 28 2019 at 14:16)</a>:</h4>
<p>Right, I agree; -- the current/PR behavior does not conform exactly with the specification I gave above, but importantly we move in all respects towards that spec and never away from it, I think.</p>



<a name="169228257"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228257" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228257">(Jun 28 2019 at 14:16)</a>:</h4>
<p>my understanding is that such cases today are not handled, at least not without a feature-flag</p>



<a name="169228309"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228309" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228309">(Jun 28 2019 at 14:17)</a>:</h4>
<p>that is correct, <span class="user-mention" data-user-id="116083">@pnkfelix</span>, although I think they would not yield any surprises over (e.g.) <code>Box&lt;&amp;Self&gt;</code></p>



<a name="169228356"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228356" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228356">(Jun 28 2019 at 14:18)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> actually we have:</p>
<div class="codehilite"><pre><span></span><span class="k">fn</span> <span class="nf">pin_pin_pin_ref</span><span class="p">(</span><span class="bp">self</span>: <span class="nc">Pin</span><span class="o">&lt;</span><span class="n">Pin</span><span class="o">&lt;</span><span class="n">Pin</span><span class="o">&lt;&amp;</span><span class="n">Self</span><span class="o">&gt;&gt;&gt;</span><span class="p">)</span><span class="w"> </span>-&gt; <span class="nc">Pin</span><span class="o">&lt;</span><span class="n">Pin</span><span class="o">&lt;</span><span class="n">Pin</span><span class="o">&lt;&amp;</span><span class="n">Self</span><span class="o">&gt;&gt;&gt;</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="bp">self</span><span class="w"> </span><span class="p">}</span><span class="w"></span>
</pre></div>



<a name="169228358"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228358" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228358">(Jun 28 2019 at 14:18)</a>:</h4>
<p>well... <code>Box&lt;&amp;Self&gt;</code> is one of the cases that changes its behavior in <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a></p>



<a name="169228435"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228435" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228435">(Jun 28 2019 at 14:18)</a>:</h4>
<p>and therefore that is not putting much of a bound on how much surprise I might suffer</p>



<a name="169228454"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228454" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228454">(Jun 28 2019 at 14:18)</a>:</h4>
<p>sorry, what I mean is that adding additional layers of <code>Box</code> does not change anything</p>



<a name="169228464"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228464" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228464">(Jun 28 2019 at 14:18)</a>:</h4>
<p>but it'd be good to show at least one more :)</p>



<a name="169228503"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228503" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228503">(Jun 28 2019 at 14:19)</a>:</h4>
<p>The only stable recursive case is for Pin per snippet above</p>



<a name="169228507"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228507" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228507">(Jun 28 2019 at 14:19)</a>:</h4>
<blockquote>
<p><span class="user-mention silent" data-user-id="116083">pnkfelix</span> actually we have:</p>
<div class="codehilite"><pre><span></span><span class="k">fn</span> <span class="nf">pin_pin_pin_ref</span><span class="p">(</span><span class="bp">self</span>: <span class="nc">Pin</span><span class="o">&lt;</span><span class="n">Pin</span><span class="o">&lt;</span><span class="n">Pin</span><span class="o">&lt;&amp;</span><span class="n">Self</span><span class="o">&gt;&gt;&gt;</span><span class="p">)</span><span class="w"> </span>-&gt; <span class="nc">Pin</span><span class="o">&lt;</span><span class="n">Pin</span><span class="o">&lt;</span><span class="n">Pin</span><span class="o">&lt;&amp;</span><span class="n">Self</span><span class="o">&gt;&gt;&gt;</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="bp">self</span><span class="w"> </span><span class="p">}</span><span class="w"></span>
</pre></div>


</blockquote>
<p>So that <em>is</em> supported without a feature gate?</p>



<a name="169228515"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228515" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228515">(Jun 28 2019 at 14:19)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> yes, there's a test for it in the PR</p>



<a name="169228523"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228523" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228523">(Jun 28 2019 at 14:19)</a>:</h4>
<p>okay</p>



<a name="169228531"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228531" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228531">(Jun 28 2019 at 14:19)</a>:</h4>
<p>(and I think this is correct)</p>



<a name="169228653"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228653" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228653">(Jun 28 2019 at 14:20)</a>:</h4>
<p>Checking the PR quickly it also has tests for aliases and whatnot</p>



<a name="169228673"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228673" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228673">(Jun 28 2019 at 14:21)</a>:</h4>
<p>It doesn't test for more feature gated cases, but we can follow up for that</p>



<a name="169228675"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228675" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228675">(Jun 28 2019 at 14:21)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> so, what are the misgivings you'd like to discuss? Are they misgivings with PR <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a>? Or are they misgivings with the current state of affairs, i.e. a desire for us to make breaking changes <em>in the future</em> ?</p>



<a name="169228815"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228815" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228815">(Jun 28 2019 at 14:23)</a>:</h4>
<p>I dont' think I have misgivings with the PR as is. I have misgivings around our current behavior</p>



<a name="169228834"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228834" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228834">(Jun 28 2019 at 14:23)</a>:</h4>
<p>and the PR does not correct all of those misgivings</p>



<a name="169228859"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228859" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228859">(Jun 28 2019 at 14:23)</a>:</h4>
<p>Okay. So that's fine, that's an argument that more work needs to be done in the long term</p>



<a name="169228876"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228876" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228876">(Jun 28 2019 at 14:23)</a>:</h4>
<p>potentially with, e.g., warning-cycled changes</p>



<a name="169228890"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228890" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228890">(Jun 28 2019 at 14:23)</a>:</h4>
<p>correct</p>



<a name="169228955"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228955" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228955">(Jun 28 2019 at 14:24)</a>:</h4>
<p>So I guess then the question is whether to backport: the changes seem fairly self-contained</p>



<a name="169228963"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169228963" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169228963">(Jun 28 2019 at 14:24)</a>:</h4>
<p>OK so we've answered 1. "we think the PR is a strict improvement"</p>



<a name="169229030"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229030" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229030">(Jun 28 2019 at 14:25)</a>:</h4>
<blockquote>
<p>So I guess then the question is whether to backport: the changes seem fairly self-contained</p>
</blockquote>
<p>and also, whether to backport to 1.36? Or if the backport can target 1.37 instead. (As <span class="user-mention" data-user-id="126931">@centril</span> stated up above in the list of questions to resolve)</p>



<a name="169229060"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229060" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229060">(Jun 28 2019 at 14:25)</a>:</h4>
<p>I am pretty convinced from what e.g. <span class="user-mention" data-user-id="127859">@Taylor Cramer</span> has said that we <em>do</em> want something landed in time for 1.37</p>



<a name="169229129"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229129" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229129">(Jun 28 2019 at 14:26)</a>:</h4>
<p>and <span class="user-mention" data-user-id="126931">@centril</span> was saying last night at the T-lang meeting that they were willing to take the heat on the release team for trying to get PR <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a> backported into 1.36</p>



<a name="169229131"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229131" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229131">(Jun 28 2019 at 14:26)</a>:</h4>
<p>I think we should target 1.37 personally</p>



<a name="169229149"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229149" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229149">(Jun 28 2019 at 14:26)</a>:</h4>
<p>Er, wait</p>



<a name="169229158"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229158" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229158">(Jun 28 2019 at 14:26)</a>:</h4>
<p>Sorry, 1.36 is current beta, correct?</p>



<a name="169229159"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229159" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229159">(Jun 28 2019 at 14:26)</a>:</h4>
<p>shall we perhaps briefly discuss the pros and cons of 1.36 vs 1.37 ?</p>



<a name="169229175"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229175" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229175">(Jun 28 2019 at 14:27)</a>:</h4>
<p>1.36 is the imminent release</p>



<a name="169229197"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229197" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229197">(Jun 28 2019 at 14:27)</a>:</h4>
<p>Yes, so the argument for 1.36 in <em>particular</em> (since the behavior in question is already stabilized) is that <code>Future</code> trait is stabilized there</p>



<a name="169229203"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229203" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229203">(Jun 28 2019 at 14:27)</a>:</h4>
<p>We have a clean crater run</p>



<a name="169229246"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229246" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229246">(Jun 28 2019 at 14:28)</a>:</h4>
<p>But it's pretty plausible that there a lot more code that relies on the stable behavior would be producd between 1.36 and 1.37</p>



<a name="169229277"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229277" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229277">(Jun 28 2019 at 14:28)</a>:</h4>
<p>Pietro and Mark were OK with backport it seems -- but we have some CI problems and making a new stable release after the 30th will be hard; so we need to act fast, basically</p>



<a name="169229284"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229284" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229284">(Jun 28 2019 at 14:28)</a>:</h4>
<p>I hate to ask the question, but I feel like I must: It would be a non-starter to unstabilize <code>Future</code> in 1.36 based on this, right?</p>



<a name="169229288"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229288" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229288">(Jun 28 2019 at 14:28)</a>:</h4>
<p>eheheh :D</p>



<a name="169229305"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229305" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229305">(Jun 28 2019 at 14:28)</a>:</h4>
<p>(I mean as an alternative to landing <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a> right now into 1.36)</p>



<a name="169229329"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229329" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229329">(Jun 28 2019 at 14:29)</a>:</h4>
<p>Interesting, I had not considered that. :)</p>



<a name="169229330"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229330" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229330">(Jun 28 2019 at 14:29)</a>:</h4>
<p>It seems somehow riskier</p>



<a name="169229334"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229334" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229334">(Jun 28 2019 at 14:29)</a>:</h4>
<p>socially or technically?</p>



<a name="169229338"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229338" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229338">(Jun 28 2019 at 14:29)</a>:</h4>
<p>I guess it's just adding a stability attribute on</p>



<a name="169229352"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229352" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229352">(Jun 28 2019 at 14:29)</a>:</h4>
<p>I meant technically but also socially :)</p>



<a name="169229361"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229361" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229361">(Jun 28 2019 at 14:29)</a>:</h4>
<p>I don't know what other components we are landing rely on it being stable</p>



<a name="169229363"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229363" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229363">(Jun 28 2019 at 14:29)</a>:</h4>
<p>Like, we have a PR with a crater run</p>



<a name="169229375"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229375" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229375">(Jun 28 2019 at 14:29)</a>:</h4>
<p>It is relatively contained</p>



<a name="169229430"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229430" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229430">(Jun 28 2019 at 14:30)</a>:</h4>
<p>the chance of a "whooops, we didn't think of <em>that</em>" with destabilizing <code>Future</code> trait seems higher</p>



<a name="169229438"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229438" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229438">(Jun 28 2019 at 14:30)</a>:</h4>
<p>I guess it depends on the confidence with which we claim the PR is a strict improvement</p>



<a name="169229444"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229444" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229444">(Jun 28 2019 at 14:30)</a>:</h4>
<p>Destabilizing Future seems easy tho if we must</p>



<a name="169229486"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229486" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229486">(Jun 28 2019 at 14:31)</a>:</h4>
<p>I've perhaps just been burned too many times by breaking the build with a "harmless change that could never break anything" :)</p>



<a name="169229514"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229514" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229514">(Jun 28 2019 at 14:31)</a>:</h4>
<p>In any case, there are also social considerations to consider, yes :)</p>



<a name="169229525"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229525" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229525">(Jun 28 2019 at 14:32)</a>:</h4>
<p>that'd be a much bigger announcement to be planned</p>



<a name="169229583"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229583" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229583">(Jun 28 2019 at 14:32)</a>:</h4>
<p>the stable surface area of arbitrary self types is, I believe, restrained to compositions of <code>Box</code>, <code>&amp;</code>, <code>&amp;mut</code>, and <code>Pin</code></p>



<a name="169229607"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229607" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229607">(Jun 28 2019 at 14:32)</a>:</h4>
<p>(Box is not recursive, Pin is)</p>



<a name="169229814"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229814" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229814">(Jun 28 2019 at 14:35)</a>:</h4>
<p>and what does <code>Box&lt;Pin&lt;&amp;Self&gt;&gt;</code> do?</p>



<a name="169229822"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229822" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229822">(Jun 28 2019 at 14:35)</a>:</h4>
<p>what do you mean not recursive?</p>



<a name="169229824"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229824" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229824">(Jun 28 2019 at 14:35)</a>:</h4>
<blockquote>
<p>and what does <code>Box&lt;Pin&lt;&amp;Self&gt;&gt;</code> do?</p>
</blockquote>
<p>testing that now :)</p>



<a name="169229884"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229884" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229884">(Jun 28 2019 at 14:36)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> <code>self: Box&lt;Box&lt;Self&gt;&gt;</code> is an error on stable, I think?</p>



<a name="169229912"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229912" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229912">(Jun 28 2019 at 14:36)</a>:</h4>
<p>ah, I see</p>



<a name="169229915"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229915" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229915">(Jun 28 2019 at 14:36)</a>:</h4>
<p>yes, that is correct</p>



<a name="169229920"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229920" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229920">(Jun 28 2019 at 14:36)</a>:</h4>
<p>(correct, it is)</p>



<a name="169229929"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229929" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229929">(Jun 28 2019 at 14:36)</a>:</h4>
<blockquote>
<p>and what does <code>Box&lt;Pin&lt;&amp;Self&gt;&gt;</code> do?</p>
</blockquote>
<p>with the feature-gate, it matches against the <code>&amp;</code> from <code>&amp;Self</code> (as I would expect)</p>



<a name="169229960"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229960" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229960">(Jun 28 2019 at 14:37)</a>:</h4>
<p>point is, the stable surface is more shallow than I thought, <span class="user-mention" data-user-id="126931">@centril</span> ?</p>



<a name="169229968"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169229968" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169229968">(Jun 28 2019 at 14:37)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> yup</p>



<a name="169230007"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230007" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230007">(Jun 28 2019 at 14:38)</a>:</h4>
<p>This test (<code>src/test/ui/self/self_lifetime.rs</code>) looks strange:</p>
<div class="codehilite"><pre><span></span><span class="k">struct</span> <span class="nc">Foo</span><span class="o">&lt;</span><span class="na">&#39;a</span><span class="o">&gt;</span><span class="p">(</span><span class="o">&amp;</span><span class="na">&#39;a</span><span class="w"> </span><span class="p">());</span><span class="w"></span>
<span class="k">impl</span><span class="o">&lt;</span><span class="na">&#39;a</span><span class="o">&gt;</span><span class="w"> </span><span class="n">Foo</span><span class="o">&lt;</span><span class="na">&#39;a</span><span class="o">&gt;</span><span class="w"> </span><span class="p">{</span><span class="w"></span>
<span class="w">    </span><span class="k">fn</span> <span class="nf">foo</span><span class="o">&lt;</span><span class="na">&#39;b</span><span class="o">&gt;</span><span class="p">(</span><span class="bp">self</span>: <span class="kp">&amp;</span><span class="na">&#39;b</span><span class="w"> </span><span class="n">Foo</span><span class="o">&lt;</span><span class="na">&#39;a</span><span class="o">&gt;</span><span class="p">)</span><span class="w"> </span>-&gt; <span class="kp">&amp;</span><span class="p">()</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="bp">self</span><span class="p">.</span><span class="mi">0</span><span class="w"> </span><span class="p">}</span><span class="w"></span>
<span class="p">}</span><span class="w"></span>

<span class="k">type</span> <span class="nc">Alias</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">Foo</span><span class="o">&lt;</span><span class="nb">&#39;static</span><span class="o">&gt;</span><span class="p">;</span><span class="w"></span>
<span class="k">impl</span><span class="w"> </span><span class="n">Alias</span><span class="w"> </span><span class="p">{</span><span class="w"></span>
<span class="w">    </span><span class="k">fn</span> <span class="nf">bar</span><span class="o">&lt;</span><span class="na">&#39;a</span><span class="o">&gt;</span><span class="p">(</span><span class="bp">self</span>: <span class="kp">&amp;</span><span class="nc">Alias</span><span class="p">,</span><span class="w"> </span><span class="n">arg</span>: <span class="kp">&amp;</span><span class="na">&#39;a</span><span class="w"> </span><span class="p">())</span><span class="w"> </span>-&gt; <span class="kp">&amp;</span><span class="p">()</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="n">arg</span><span class="w"> </span><span class="p">}</span><span class="w"></span>
<span class="p">}</span><span class="w"></span>
</pre></div>



<a name="169230061"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230061" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230061">(Jun 28 2019 at 14:38)</a>:</h4>
<p>(added in the PR, but the behavior is the same on stable)</p>



<a name="169230078"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230078" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230078">(Jun 28 2019 at 14:38)</a>:</h4>
<p>I agree that behavior is strange</p>



<a name="169230080"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230080" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230080">(Jun 28 2019 at 14:38)</a>:</h4>
<p>this is the case I was pointing out</p>



<a name="169230085"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230085" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230085">(Jun 28 2019 at 14:38)</a>:</h4>
<p>right</p>



<a name="169230088"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230088" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230088">(Jun 28 2019 at 14:38)</a>:</h4>
<p>rwell</p>



<a name="169230090"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230090" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230090">(Jun 28 2019 at 14:38)</a>:</h4>
<p>well</p>



<a name="169230093"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230093" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230093">(Jun 28 2019 at 14:38)</a>:</h4>
<p>actually it's not quite</p>



<a name="169230117"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230117" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230117">(Jun 28 2019 at 14:39)</a>:</h4>
<p>that surprises me a little</p>



<a name="169230135"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230135" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230135">(Jun 28 2019 at 14:39)</a>:</h4>
<p>I think that <code>&amp;Alias</code> does not count as "self" type</p>



<a name="169230138"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230138" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230138">(Jun 28 2019 at 14:39)</a>:</h4>
<p>this is a distinct case</p>



<a name="169230201"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230201" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230201">(Jun 28 2019 at 14:40)</a>:</h4>
<p>regardless I do not think the PR changes anything in this regard</p>



<a name="169230205"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230205" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230205">(Jun 28 2019 at 14:40)</a>:</h4>
<p>indeed</p>



<a name="169230209"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230209" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230209">(Jun 28 2019 at 14:40)</a>:</h4>
<p>except extending the strangeness to things like <code>Pin&lt;&amp;Alias&gt;</code></p>



<a name="169230233"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230233" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230233">(Jun 28 2019 at 14:40)</a>:</h4>
<div class="codehilite"><pre><span></span><span class="k">impl</span><span class="w"> </span><span class="n">Alias</span><span class="w"> </span><span class="p">{</span><span class="w"></span>
<span class="w">    </span><span class="k">fn</span> <span class="nf">bar</span><span class="o">&lt;</span><span class="na">&#39;a</span><span class="o">&gt;</span><span class="p">(</span><span class="bp">self</span>: <span class="kp">&amp;</span><span class="nc">Self</span><span class="p">,</span><span class="w"> </span><span class="n">arg</span>: <span class="kp">&amp;</span><span class="na">&#39;a</span><span class="w"> </span><span class="p">())</span><span class="w"> </span>-&gt; <span class="kp">&amp;</span><span class="p">()</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="n">arg</span><span class="w"> </span><span class="p">}</span><span class="w"></span>
<span class="p">}</span><span class="w"></span>
</pre></div>


<p>gets rejected</p>



<a name="169230248"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230248" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230248">(Jun 28 2019 at 14:40)</a>:</h4>
<p>(I'm actually not sure this is bad, I think I might prefer to deprecate all cases around elision except with the keyword <code>Self</code>, personally)</p>



<a name="169230275"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230275" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230275">(Jun 28 2019 at 14:41)</a>:</h4>
<p>(but that's more the long-term question)</p>



<a name="169230303"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230303" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230303">(Jun 28 2019 at 14:41)</a>:</h4>
<p>we were having a hard time trying to explain that to <span class="user-mention" data-user-id="127859">@Taylor Cramer</span> last night</p>



<a name="169230353"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230353" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230353">(Jun 28 2019 at 14:41)</a>:</h4>
<p>(about <em>why</em> one might treat <code>Self</code> differently from <code>Foo&lt;'a&gt;</code> when <code>Self = Foo&lt;'a&gt;</code>)</p>



<a name="169230354"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230354" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230354">(Jun 28 2019 at 14:41)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span>  right; I think we should either be entirely semantic in determining <code>is_self_type</code> or entirely syntactic (the literal <code>Self</code>)</p>



<a name="169230430"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230430" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230430">(Jun 28 2019 at 14:42)</a>:</h4>
<p>that does at least sound like something we can emit a nice diagnostic for</p>



<a name="169230438"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230438" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230438">(Jun 28 2019 at 14:42)</a>:</h4>
<p>and have rustfix fix up</p>



<a name="169230527"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230527" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230527">(Jun 28 2019 at 14:43)</a>:</h4>
<p>I've updated the chart to include this case</p>



<a name="169230530"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230530" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230530">(Jun 28 2019 at 14:43)</a>:</h4>
<p>(S9)</p>



<a name="169230595"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230595" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230595">(Jun 28 2019 at 14:44)</a>:</h4>
<p>so I personally think a backport is ok</p>



<a name="169230602"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230602" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230602">(Jun 28 2019 at 14:44)</a>:</h4>
<p>I think I would prefer that to destabilizing future</p>



<a name="169230615"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230615" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230615">(Jun 28 2019 at 14:44)</a>:</h4>
<p>which feels like a heavier lift, socially plus technically, <em>plus</em> still leaves "undesirable" behavior on stable longer</p>



<a name="169230631"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230631" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230631">(Jun 28 2019 at 14:44)</a>:</h4>
<p>and specifically, you mean a backport to 1.36</p>



<a name="169230633"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230633" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230633">(Jun 28 2019 at 14:44)</a>:</h4>
<p>yes</p>



<a name="169230681"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230681" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230681">(Jun 28 2019 at 14:45)</a>:</h4>
<p>OK; so based on this discussion and reviewing the tests in the PR I am confident that it's a strict improvement that is also well tested. Coupled with the crater run with no regressions... I agree that a backport is OK (and personally I think it's desirable and within our time constraints).</p>



<a name="169230763"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230763" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230763">(Jun 28 2019 at 14:46)</a>:</h4>
<p>okay then. So I'll go mark the PR as beta-accepted (and include a note that we're talking about 1.36)</p>



<a name="169230772"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230772" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230772">(Jun 28 2019 at 14:46)</a>:</h4>
<p>who will prep the beta backport PR?</p>



<a name="169230783"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230783" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230783">(Jun 28 2019 at 14:46)</a>:</h4>
<p>it should be straightforward</p>



<a name="169230798"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230798" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230798">(Jun 28 2019 at 14:46)</a>:</h4>
<p>Can any of you two?</p>



<a name="169230806"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230806" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230806">(Jun 28 2019 at 14:46)</a>:</h4>
<p>I can do it now</p>



<a name="169230809"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230809" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230809">(Jun 28 2019 at 14:46)</a>:</h4>
<p><span aria-label="heart" class="emoji emoji-2764" role="img" title="heart">:heart:</span></p>



<a name="169230813"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230813" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230813">(Jun 28 2019 at 14:46)</a>:</h4>
<p>I also have a bevy of tests to add</p>



<a name="169230822"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230822" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230822">(Jun 28 2019 at 14:47)</a>:</h4>
<p>but I will not do that as part of backport</p>



<a name="169230837"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230837" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230837">(Jun 28 2019 at 14:47)</a>:</h4>
<p>awesome!</p>



<a name="169230859"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230859" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230859">(Jun 28 2019 at 14:47)</a>:</h4>
<p>one other thing I want to bring up but only briefly</p>



<a name="169230876"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230876" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230876">(Jun 28 2019 at 14:47)</a>:</h4>
<p>is that I think we should try to "follow up" with deprecation warnings for some of the other behaviors</p>



<a name="169230882"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230882" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230882">(Jun 28 2019 at 14:47)</a>:</h4>
<p>i.e., let's put this "to bed"</p>



<a name="169230891"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230891" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230891">(Jun 28 2019 at 14:48)</a>:</h4>
<p>this doesn't have the "time pressure" aspect</p>



<a name="169230942"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230942" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230942">(Jun 28 2019 at 14:48)</a>:</h4>
<p>and maybe wants an RFC</p>



<a name="169230960"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230960" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230960">(Jun 28 2019 at 14:48)</a>:</h4>
<p>I'm not sure about the semantic/syntactic <code>Self</code> question personally but I agree with "let's settle the matter permanently"</p>



<a name="169230963"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230963" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230963">(Jun 28 2019 at 14:48)</a>:</h4>
<p>I'm sort of inclined to just "deprecate" weird behaviors for now, maybe remove in an edition or something</p>



<a name="169230981"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169230981" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169230981">(Jun 28 2019 at 14:48)</a>:</h4>
<blockquote>
<p>I'm not sure about the semantic/syntactic <code>Self</code> question personally but I agree with "let's settle the matter permanently"</p>
</blockquote>
<p>I agree</p>



<a name="169231008"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231008" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231008">(Jun 28 2019 at 14:49)</a>:</h4>
<p>there are a few other minor things; e.g., right now you can do <code>fn foo&lt;'a&gt;(x: &amp;'a self) -&gt; &amp;u8</code>, which I think should be forbidden (use <code>'a</code>)</p>



<a name="169231013"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231013" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231013">(Jun 28 2019 at 14:49)</a>:</h4>
<p>well, I think should be linted</p>



<a name="169231030"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231030" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231030">(Jun 28 2019 at 14:49)</a>:</h4>
<p>Linting on that one seems reasonable at least imo</p>



<a name="169231031"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231031" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231031">(Jun 28 2019 at 14:49)</a>:</h4>
<p>many of these were already discussed on and off</p>



<a name="169231057"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231057" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231057">(Jun 28 2019 at 14:50)</a>:</h4>
<p>this is more something to put on lang team agenda I think, though</p>



<a name="169231112"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231112" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231112">(Jun 28 2019 at 14:50)</a>:</h4>
<p>as a possible "focus topic" for some group to go and take care of</p>



<a name="169231120"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231120" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231120">(Jun 28 2019 at 14:50)</a>:</h4>
<p>let me go prep that PR</p>



<a name="169231126"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231126" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231126">(Jun 28 2019 at 14:50)</a>:</h4>
<p>before I get distraced :P</p>



<a name="169231154"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231154" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231154">(Jun 28 2019 at 14:50)</a>:</h4>
<p>Yeah; I think this <code>fn foo</code> example has the problem of being confusing when you don't know the rules by heart</p>



<a name="169231203"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231203" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231203">(Jun 28 2019 at 14:51)</a>:</h4>
<blockquote>
<p>before I get distraced :P</p>
</blockquote>
<p>or even DTraced</p>



<a name="169231236"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231236" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231236">(Jun 28 2019 at 14:51)</a>:</h4>
<p>(can you tell I was up until 3am)</p>



<a name="169231240"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231240" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231240">(Jun 28 2019 at 14:51)</a>:</h4>
<p>BTW <span class="user-mention" data-user-id="126931">@centril</span> I refined your description</p>



<a name="169231242"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231242" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231242">(Jun 28 2019 at 14:51)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span>  great blog post btw!</p>



<a name="169231245"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231245" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231245">(Jun 28 2019 at 14:51)</a>:</h4>
<ul>
<li>61207: In the receiver, if all mentions of the semantic type <code>&amp;'lt mut? Self</code> use a unique lifetime <code>'lt</code>, then <code>'lt</code> is assigned to all elided output lifetime parameters.</li>
</ul>



<a name="169231303"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231303" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231303">(Jun 28 2019 at 14:52)</a>:</h4>
<blockquote>
<p>great blog post btw!</p>
</blockquote>
<p>where was it posted?</p>



<a name="169231322"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231322" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231322">(Jun 28 2019 at 14:52)</a>:</h4>
<blockquote>
<ul>
<li>61207: In the receiver, if all mentions of the semantic type <code>&amp;'lt mut? Self</code> use a unique lifetime <code>'lt</code>, then <code>'lt</code> is assigned to all elided output lifetime parameters.</li>
</ul>
</blockquote>
<p>it's not possible for this to be relevant on stable, but it matters with the feature gate enabled</p>



<a name="169231329"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231329" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231329">(Jun 28 2019 at 14:52)</a>:</h4>
<blockquote>
<p>where was it posted?</p>
</blockquote>
<p><a href="http://blog.pnkfx.org/" target="_blank" title="http://blog.pnkfx.org/">http://blog.pnkfx.org/</a></p>



<a name="169231341"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231341" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231341">(Jun 28 2019 at 14:52)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> <a href="http://blog.pnkfx.org/blog/2019/06/26/breaking-news-non-lexical-lifetimes-arrives-for-everyone/" target="_blank" title="http://blog.pnkfx.org/blog/2019/06/26/breaking-news-non-lexical-lifetimes-arrives-for-everyone/">http://blog.pnkfx.org/blog/2019/06/26/breaking-news-non-lexical-lifetimes-arrives-for-everyone/</a></p>



<a name="169231350"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231350" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231350">(Jun 28 2019 at 14:52)</a>:</h4>
<p>&lt;3</p>



<a name="169231368"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231368" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231368">(Jun 28 2019 at 14:53)</a>:</h4>
<p>I continue to be quite proud of getting those Tufte margin notes to work</p>



<a name="169231460"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231460" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231460">(Jun 28 2019 at 14:54)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> the description probably needs a definition of "semantic type" also since aliases didn't work</p>



<a name="169231470"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231470" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231470">(Jun 28 2019 at 14:54)</a>:</h4>
<p>(which I expected it would when I wrote this)</p>



<a name="169231532"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231532" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231532">(Jun 28 2019 at 14:55)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span>  btw, the backport target should be the <code>stable</code> branch, I think</p>



<a name="169231553"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231553" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231553">(Jun 28 2019 at 14:55)</a>:</h4>
<blockquote>
<p><span class="user-mention silent" data-user-id="116009">nikomatsakis</span> the description probably needs a definition of "semantic type" also since aliases didn't work</p>
</blockquote>
<p>yes so the actual test is "the path <code>Self</code> or a path that resolves to the struct/enum/union"</p>



<a name="169231562"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231562" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231562">(Jun 28 2019 at 14:56)</a>:</h4>
<blockquote>
<p><span class="user-mention silent" data-user-id="116009">nikomatsakis</span>  btw, the backport target should be the <code>stable</code> branch, I think</p>
</blockquote>
<p>oh, ok</p>



<a name="169231635"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231635" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231635">(Jun 28 2019 at 14:56)</a>:</h4>
<p>(because we have already done the beta -&gt; stable promotion)</p>



<a name="169231648"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231648" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231648">(Jun 28 2019 at 14:56)</a>:</h4>
<blockquote>
<p>yes so the actual test is "the path <code>Self</code> or a path that resolves to the struct/enum/union"</p>
</blockquote>
<p>note that this is <em>not</em> necessarily <code>Self</code> (as I noted in the gist below)</p>



<a name="169231654"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231654" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231654">(Jun 28 2019 at 14:56)</a>:</h4>
<p>(that is, <code>stable</code> and <code>beta</code> point at the same place atm)</p>



<a name="169231663"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231663" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231663">(Jun 28 2019 at 14:56)</a>:</h4>
<p>they...don't</p>



<a name="169231668"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231668" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231668">(Jun 28 2019 at 14:57)</a>:</h4>
<p>at least I don't think they do</p>



<a name="169231670"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231670" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231670">(Jun 28 2019 at 14:57)</a>:</h4>
<blockquote>
<p>(that is, <code>stable</code> and <code>beta</code> point at the same place atm)</p>
</blockquote>
<p>but won't he need to land it in both places?</p>



<a name="169231707"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231707" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231707">(Jun 28 2019 at 14:57)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> yes, but land on stable first, then nightly</p>



<a name="169231713"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231713" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231713">(Jun 28 2019 at 14:57)</a>:</h4>
<p>and then nightly gets promoted to beta</p>



<a name="169231724"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231724" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231724">(Jun 28 2019 at 14:57)</a>:</h4>
<p>ah right, we haven't promoted nightly to beta yet</p>



<a name="169231726"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231726" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231726">(Jun 28 2019 at 14:57)</a>:</h4>
<p>okay</p>



<a name="169231806"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231806" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231806">(Jun 28 2019 at 14:58)</a>:</h4>
<div class="codehilite"><pre><span></span>athena. git log rust-lang/stable <span class="p">|</span> head
commit 09a353c529064185aab3fee18128cf1cc697c11e
Merge: 83167c47939 32055e1cd98
Author: bors &lt;bors@rust-lang.org&gt;
Date:   Wed Jun <span class="m">26</span> <span class="m">22</span>:52:15 <span class="m">2019</span> +0000

    Auto merge of <span class="c1">#62162 - Mark-Simulacrum:stable-next, r=Mark-Simulacrum</span>

    <span class="o">[</span>stable<span class="o">]</span> <span class="m">1</span>.36 stable release

    cc @rust-lang/release
</pre></div>



<a name="169231817"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231817" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231817">(Jun 28 2019 at 14:58)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span>  oh yeah, you are correct</p>



<a name="169231832"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231832" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231832">(Jun 28 2019 at 14:58)</a>:</h4>
<p>but that's just switching the "is it stable"</p>



<a name="169231835"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231835" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231835">(Jun 28 2019 at 14:58)</a>:</h4>
<p>Not sure if that means I should target stable or not</p>



<a name="169231839"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231839" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231839">(Jun 28 2019 at 14:58)</a>:</h4>
<p>right</p>



<a name="169231843"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231843" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231843">(Jun 28 2019 at 14:58)</a>:</h4>
<p>ok</p>



<a name="169231848"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231848" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231848">(Jun 28 2019 at 14:58)</a>:</h4>
<p>so they are morally equivalent</p>



<a name="169231854"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231854" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231854">(Jun 28 2019 at 14:58)</a>:</h4>
<p>yep</p>



<a name="169231860"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231860" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231860">(Jun 28 2019 at 14:58)</a>:</h4>
<p>==&gt; target stable</p>



<a name="169231875"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231875" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231875">(Jun 28 2019 at 14:59)</a>:</h4>
<p>so should I use rust-lang/stable as the basis for my PR?</p>



<a name="169231882"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231882" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231882">(Jun 28 2019 at 14:59)</a>:</h4>
<p>I guess the merge will only bring in the fresh commits</p>



<a name="169231883"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169231883" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169231883">(Jun 28 2019 at 14:59)</a>:</h4>
<p>so it's fine</p>



<a name="169232115"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232115" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232115">(Jun 28 2019 at 15:01)</a>:</h4>
<p>OK I opened <a href="https://github.com/rust-lang/rust/pull/62209" target="_blank" title="https://github.com/rust-lang/rust/pull/62209">https://github.com/rust-lang/rust/pull/62209</a></p>



<a name="169232126"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232126" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232126">(Jun 28 2019 at 15:01)</a>:</h4>
<p>I would be ok with r+'ing <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a></p>



<a name="169232230"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232230" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232230">(Jun 28 2019 at 15:03)</a>:</h4>
<p>r+ed</p>



<a name="169232326"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232326" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232326">(Jun 28 2019 at 15:04)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> did you want to push your bevy of new tests to <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a> first before r+'ing?</p>



<a name="169232335"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232335" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232335">(Jun 28 2019 at 15:04)</a>:</h4>
<p>good idea</p>



<a name="169232342"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232342" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232342">(Jun 28 2019 at 15:04)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span>  What a nice and clean backport :D</p>



<a name="169232346"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232346" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232346">(Jun 28 2019 at 15:04)</a>:</h4>
<blockquote>
<p><span class="user-mention silent" data-user-id="116009">nikomatsakis</span> did you want to push your bevy of new tests to <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a> first before r+'ing?</p>
</blockquote>
<p>I was going to ask whether I should do that</p>



<a name="169232348"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232348" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232348">(Jun 28 2019 at 15:04)</a>:</h4>
<p>I'll babysit it</p>



<a name="169232349"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232349" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232349">(Jun 28 2019 at 15:04)</a>:</h4>
<p>I would be happy to do so</p>



<a name="169232379"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232379" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232379">(Jun 28 2019 at 15:05)</a>:</h4>
<p>I have a dentist appointment soon so I'll be afk for a bit but I'll try do those tests now before I go</p>



<a name="169232380"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232380" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232380">(Jun 28 2019 at 15:05)</a>:</h4>
<p>I think it would be a good idea to get those tests in</p>



<a name="169232391"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232391" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232391">(Jun 28 2019 at 15:05)</a>:</h4>
<p>okay thanks</p>



<a name="169232416"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232416" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232416">(Jun 28 2019 at 15:05)</a>:</h4>
<p>Yeah, thanks</p>



<a name="169232856"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169232856" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169232856">(Jun 28 2019 at 15:10)</a>:</h4>
<p><span class="user-mention" data-user-id="116122">@simulacrum</span>  So I r+ed <a href="https://github.com/rust-lang/rust/pull/62209" target="_blank" title="https://github.com/rust-lang/rust/pull/62209">https://github.com/rust-lang/rust/pull/62209</a> but I'm not familiar with dev-static and the other stuff</p>



<a name="169233475"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169233475" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169233475">(Jun 28 2019 at 15:18)</a>:</h4>
<p>also cc <span class="user-mention" data-user-id="121055">@Pietro Albini</span></p>



<a name="169233515"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169233515" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Pietro Albini <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169233515">(Jun 28 2019 at 15:18)</a>:</h4>
<p><span class="user-mention" data-user-id="126931">@centril</span> ping me once it's merged</p>



<a name="169233521"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169233521" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169233521">(Jun 28 2019 at 15:19)</a>:</h4>
<p>will do</p>



<a name="169233543"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169233543" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Pietro Albini <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169233543">(Jun 28 2019 at 15:19)</a>:</h4>
<p>nuking the dev-static's channel toml should be enough</p>



<a name="169252581"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169252581" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169252581">(Jun 28 2019 at 18:58)</a>:</h4>
<p><span class="user-mention" data-user-id="126931">@centril</span> I pushed tests to <a href="https://github.com/rust-lang/rust/issues/61207" target="_blank" title="https://github.com/rust-lang/rust/issues/61207">#61207</a></p>



<a name="169252821"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169252821" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169252821">(Jun 28 2019 at 19:01)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span>  I saw; taking a look</p>



<a name="169255916"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169255916" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169255916">(Jun 28 2019 at 19:40)</a>:</h4>
<p><span class="user-mention" data-user-id="116009">@nikomatsakis</span> in case you didn't see on Discord, <a href="https://github.com/rust-lang/rust/pull/62209" target="_blank" title="https://github.com/rust-lang/rust/pull/62209">https://github.com/rust-lang/rust/pull/62209</a> failed and probably needs <code>--bless --compare-mode=nll</code></p>



<a name="169260440"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/steering%20meeting%202019-06-28/near/169260440" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/steering.20meeting.202019-06-28.html#169260440">(Jun 28 2019 at 20:42)</a>:</h4>
<p>Pushed a fix to your branch</p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
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